The goal of the proposed research is to develop and validate a clinically practical (brief, inexpensive, user friendly, with standardized item response format) and research-valid tool for capturing and monitoring the multi-disease symptom severity of elderly patients who attend primary care clinics through the input of two important voices: the patient and their informal caregiver. The expected outcome is a stakeholder-enhanced valid, multi-dimensional, and clinically useful tool which addresses a major gap in translational and patient-centered outcomes research. Findings from the study will bring us one step closer to our long term goal of integrating research and clinical practice. The specific aims are as follows. Specific Aim 1: Using mixed-methods (stakeholder focus groups, psychometric analyses of existing data, and input from an expert panel), develop Version 1.0 of the clinically practical Healthy Aging Care (HAC) Monitor tool for monitoring caregiver and patient reports of symptoms for older (age e 65) patients in primary care. Specific Aim 2: Using mixed-methods, field test and revise Version 1.0 of the Healthy Aging Care (HAC) Monitor using cognitive interviewing of all key stakeholders (patients, caregivers, providers) and a quantitative survey to assess usability and feasibility in a small sample of dyads (patients and their informal caregivers). Specific Aim 3: Conduct a full psychometric evaluation of the patient-reported and caregiver-reported final version (Version 2.0) of the Healthy Aging Care (HAC) Monitor to assess its internal consistency and test-retest reliability, congruence between patient and caregiver, construct validity, predictive validity of patients' health care utilization, and sensitvity to change from baseline to 3-month assessment in a larger sample of dyads (patients and their informal caregivers). The study's mixed methods design and analyses will include instrument development through focus groups, cognitive interviewing, item statistics, and expert panel judgment; usability and feasibility descriptive statistics of 40 patients and their 40 caregivers i a small-sample field testing of a telephone survey; and psychometric evaluation of reliability and validity using telephone survey data from a larger sample of 200 patients and their 200 caregivers.